A 15-year-old student in north Mexico who shot his teacher and three classmates early Wednesday before turning the gun on himself has died, local media reported.

Jaime Rodriguez, the governor of Nuevo Leon state, where the tragic school shooting occurred, told reporters at a press conference the boy was declared brain dead and removed from life support.

The teacher, 24, and two of the injured students were shot in the head and remain in critical condition, while the third victim, who was shot in the arm, is in stable condition, he said.

The attack at the American School of the Northeast was the first of its kind in the state capital of Monterrey, according to the governor.

The shooter was undergoing psychological counseling for depression. Authorities have not said how he came to have a gun.

The incident has sparked discussion about the need to resume a policy of checking students' backpacks, a measure that was cancelled after parents complained.

"We need to pay more attention to our children, and be more careful about what they carry and who they meet with, because they have access to everything online," said Rodriguez.

source: Xinhua